Note. Growth of Vibrio parahaemolyticus in lobster homogenates at different temperatures / Nota. Crecimiento de Vibrio parahaemolyticus en langosta a diferentes temperaturas

Abstract

Due to the illnesses associated with the presence of Vibrio parahaemolyticus in seafoods, its survival in lobster was studied. Lobster homogenates were prepared, sterilized, inoculated with the bacteria, and incubated at -25 °C, 6 °C and 28 °C, for 60 days. Different viable cell counting methods were employed. The results of the McFarland nephelometric standard method and the direct count of viable bacterial cells, (DVC) were not significantly different (p = 0.5). However, the DVC method was better for detecting viable cells at low numbers for longer times, especially for cultures incubated at -25 °C. Therefore, this method, and the plate count (PC) method for counting colony forming units, were selected for monitoring the survival of V. parahaemolyticus under each temperature of incuba tion. The greatest survival of the bacterium was at ambient (28 °C) temperature. At freezer tempera ture (-25 °C), no viable cells were detected towards the end of the experiments. However, the cultures kept at 6 °C were viable until the end of the incubation period, these results being different from previously published works conducted at refrigeration temperatures.